Continuous-heating furnace.



No. 67!,893. Pa tented Apr. 9, l90l. A. LAUGHLIN;

CONTINUOUS HEATING FURNACE.

(Application ,flled Sept. 17, 1900 4 Sheets-Sheet L (No Model.)

Q QW

WITNESSES:

No- 67 l,893- Patented Apr. 9, 190i. A. LAUGHLIN. CONTINUOUS HEATINGFURNACE.

(Application filed Sept. 17, 1900.;

4 Sheets-Sheet 2 (No Model WITNESSE INVENTOR,

Patented Apr. 9, I90l.

No. 67l,893.

A. LAUGHLIN. CONTINUOUS HEATING FURNACE.

(Application filed Sept 17, 1900.!

4 Sheets-Sheet 3.

(No Model.)

INVENTOR,

WITNESSES:

No. 67l,893. Patented Apr. 9, I90l.

' A. LAUGHLIN.

CONTINUOUS HEATING FURNACE.

(Application filed Sept. 17. 1900.

4 Sheets-$heef 4.

(Nu Model.)

INVENTOR,

WITNE .SES:

UNITED STATES PATENT OFFICE.

ALEXANDER LAUGHLIN, OF SEWICKLEY, PENNSYLVANIA.

CONTINUOUS-HEATING FURNACE.

SPECIFICATION forming part Of Letters Patent No. 671,893, dated April 9,1901.

Application filed September 17, 1900. Serial No. 30,281. (No model.)

To all whom it may concern.-

Be it known that I, ALEXANDER LAUGHLIN, of Sewickley, in the county ofAllegheny and State of Pennsylvania, have invented certain new anduseful Improvements in Continuous- Heating Furnaces; and I do herebydeclare the following to be a full, clear, and exact description of theinvention, such as will enable others skilled in the art to which itappertains to make and use the same.

This invention has reference to continuousheating furnaces. In thesefurnaces, as is well known, the slabs, billets, or other articles arecharged into one end and are continuously heated as they travel towardthe other end of the furnace, where they are discharged eitherautomatically or by an attendant. The supports over which the slabs,850., travel are usually equipped with pipes, through which the water iscaused to circulate to prevent injury by the heat of the furnace.Furnaces thus constructed are satisfactory where employed for heatingbillets for rod-mills, barmills, and others where the billets are rolleddown into very small sections; but when the furnace is used forheatingslabs forplate-mills the dark spots left on the slabs by the waterpipeswill, when the slab is rolled into a long wide strip, show in thefinished plate. To obviate this and remove the dark spots, furnaces havebeen provided with intermediate hearths of sand, over which the slabs,850., are caused to travel before being discharged. The successfuloperation of furnaces having hearths of sand or other refractorymaterial requires that all cinder dropping on the hearth be quicklyremoved Otherwise its accumulation prevents the pushing of the slabs orbillets in a horizontal line over the hearth, or where they areotherwise moved thereover objection arises from the fact that the sandor other material forming the hearth soon becomes spongy and it isimpossible to keep the hearth hard and smooth, which latter is essentialto good heating. Where, as is most generally the case,two lines of slabs0r billets are worked in a single furnace, the tendency is for the endsof the slabs or billets toward the longitudinal center of the furnace toget hotter than the ends toward the sides, and in consequence the cinderwill be running more freely from the slabs or billets at their innerthan modification.

at their outer ends. The slabs or billets being constantly passed overthe hearth, either in solid lines or one at a time, it is notpracticable to remove the cinder by means of grooves runningtransversely of the hearth to openings in the side walls of the furnace,especially when it is necessary to keep the hearth-surface practicallyhorizontal for the passage of a contin uousline of slabs or billets.

The object of my present improvements is to provide means for insuringthe removal of cinder from the hearth. This I accomplish by running thecinder through the bottom of the hearth. Cinder holes or pockets areformed in the body of the hearth, and the accumulated cinder isperiodically discharged preferably through doors which normally closethe lower ends of the pockets.

Preferred forms of embodiment of the invention will be hereinafter fullyset forth and the invention itself particularly pointed out in theclaims.

In the accompanying drawings, Figure 1 is a horizontal sectionalview,parts being broken away, of a furnace equipped with my presentimprovements. Fig. 2 is a vertical section on line 2 2, Fig. 1. Fig. 3is a transverse section on line 3 3, Fig. 1. Figs. 4, 5, and 6 arerespectively horizontal, vertical, and transverse sectional views of afurnace, showing a slight Figs. 7 and 8 are respectively horizontal andvertical sections of a furnace, showing a second modification. Figs. 9and 10 are enlarged vertical sectional views at right angles to eachother of portions of the hearth through a cinder-hole. Figs. 11, 12, and13 are respectively horizontal, vertical, and transverse sections of afurnace, showing a third modification.

The general construction of the furnace may be after any preferredformsuch, for instance, as is shown in reissued Letters Patent No.11,666, of May 31, 1898, or Letters Patent No. 582,477, of May 11, 1897,or Letters Patent No. 588,702, of August 24, 1897, each issued to me.

On the bed 1 are supports 2, upon which are the rails orbearing-surfaces 3, over which the slabs or billets pass transverselyfrom the charging end of the furnace, being moved grad ually through thefurnace toward the discharge end by any suitable means. The rails 3preferably consist of tubes, through which water is caused to circulate.The fuel, such as gas and air, is admitted through ports 4 at or nearthe discharge end of the furnace. The present improvement is equallyapplicable to furnaces fired direct with coal or any other fuel.

A hearth or receiving-bed 5 is located in the line of passage of theslabs and is preferably on the same horizontal plane as the adjacentends of the bearingrails; but such hearth may be considerably below theelevated supports, as shown in Figs. 12 and 13. Inclinedbearing-surfaces 5 may extend from the hearth over the ports 4 andthrough an end opening to efiect the quick automatic movement of theslabs past the ports and onto a conveyer 8, as shown and described insaid reissued Letters Patent No. 11,666. In the sides of the furnacesare door-openings 7, and adjacent to these in some instances (see Figs.1, 7, and 11) there may be the ordinary outlets 8' for the cinder whichaccumulates on the hearth. To enable all cinder to be removed from thehearth, I form the latter with tapping holes or pockets 9, which extendvertically through the hearth and its support and are normally closedattheir bottoms 01' lower ends by doors 10, mounted on arms 11, secured tocounter-shafts 12, extended to one side of the furnace. On these shafts12 are weighted arms 13, which serve to keep the doors closed, save whenit is desired to empty cinder from the holes. These cinder-holes may beformed on the same longitudinal line between the two rows of slabs (seeFig. 1) or they may be on the same transverse line directly beneath theline of passage of the slabs, (see Fig. 4,) in which event onecounter-shaft will suffice for both doors, or a single cinderhole may beemployed, as shown in Figs. 7 and 8.

The slabs may be moved over the hearth in a continuous line until theyreach the inclined rails, when they will be discharged automat-,

ieally onto the conveyer, (see Figs. 1 and 2,) or each slab as itreaches the forward ends of the rails 3 may be rolled over the hearth bythe heater or attendant until it reaches the inclined rails, as seen inFigs. 4, 5, 7, and 8, or, as shown in Figs. 11, 12, and 13, the slabsafter they fall from the elevated rails onto the hearth may be withdrawnby tongs in the usual manner through door-openings 7, the inclineddischarge-rails being omitted.

The cinder running from the slabs will be gathered in the holes,allowing continuous lines of slabs to be moved over the hearth andpreventing the sand or other refractory material of which the hearth iscomposed from becoming spongy and uneven on its upper surface. Thesecinder-holes may, if desired, be used in addition to the ordinary sideoutlets; but as they alone serve the intended purpose by being in thebottom of the hearth such side outlets are not necessary. Thecinder-holes being normally closed, cold air,

which would otherwise have a tendency to oxidize the slabs, is excluded,and the cinder is prevented from being chilled while in the holes, thusinsuring its free running when the doors are removed for that purpose.

I claim as my invention 1. In acont-inuous-heating furnace,a hearth orreceiving-bed, onto which the slabs or billets are moved before beingdischarged, having a cinder-tapping hole extending upwardly therethroughin which cinder is designed to be received, the slabs or billets beingcaused to travel over or in proximity to said hole before beingdischarged, means for so moving the slabs or billets, means for normallyclosing said hole at its lower end, and means for actuating said closingmeans for emptying said hole, as set forth.

2. Inacontinuous-heatingfurnace,ahearth or receiving-bed, onto which theslabs or billets are moved before being discharged, having acinder-tapping hole extending upwardly therethrough for the accumulationof cinder, means for so moving the slabs or billets, a door or cover forsaid hole, and means for opening said door or cover for emptying theaccumulated cinder, as set forth.

3. Inacontinuus-heatingfurnace,ahearth or receiving-bed onto which theslabs or billets are moved before being discharged, said hearth having acinder-tapping hole extending upwardly therethrough wherein cinder isdesigned to accumulate, means for so moving the slabs or billets, a dooror cover for said hole, and means at the side of the furnace for openingsuch door to discharge the accumulated cinder, substantially as setforth.

4:- Inacontinuous-heatingfurnace,a hearth or receiving-bed onto whichthe slabs or billets are moved before being discharged, said hearthhaving a cinder-tapping hole extending upwardly therethrough, means forso moving the slabs or billets, a door or cover for closing said hole,means at the side of the furnace for opening such door, and means fornormally holding the latter closed, substantially as set forth.

5. In acontinuous-heatingfurnace,ahearth, onto which the slabs orbillets are moved before being discharged, having vertically-disposedcinder -tapping holes extending upwardly therethrough in which holescinder is designed to accumulate, means for so moving the slabs orbillets, doors normally closing said holes at the lower ends, said doorsbeing designed to be periodically opened to empty the cinder from theholes, shafts to which said doors are connected, and weighted levers onsaid shafts for normally holding the doors in one position,substantially as set forth.

6. A continuous-heating furnace having a charging-opening at one end,discharge-openings at or near the other end, means for moving slabs fromthe charging end to the discharge end, a hearth or receiving-bed havinga cinder-tapping hole formed therein for the reception of cinder, meansfor moving the slabs in proximity to said hole, and means whereby thelatter may be periodically emptied of accumulated cinder, substantiallyas set forth.

7. A continuous-heating furnace having a charging-opening at one end,discharge-openings at or near the other end, bearing-rails extendinglongitudinally of the furnace, means for moving slabs over said rails,and a hearth between the charging and discharge ends in line with saidbearing rails, said hearth having cinder-tapping holes extendingupwardly therethrough, doors normally closing said holes at their lowerends, and means controllable at the side of the furnace for opening saiddoors, substantially as set forth.

8. A continuous-heating furnace having a charging-opening at one end,discharge-openings at or near the other end, two series of supports forthe slabs extending longitudinally of the furnace, means for moving theslabs over said supports, a hearth between the charging and dischargeends over which the slabs are designed to be moved, cindertapping holesformed in said hearth between the lines of passage of the slabs whereincinder is designed to accumulate, means for normally closing said holes,and means whereby said closing means may be periodically operated toempty said holes of accumulated cinder, substantially as set forth.

In testimony whereof I have signed this specification in the presence oftwo subscribing witnesses.

ALEXANDER LAUGHLIN.

Witnesses:

O. W. COFFMAN, NEWMAN GRovEs.

